Klever Kurve 10 Pack - Klever X Change Replacement Heads - Safety Cutter Replacemt Head For The Klever X Change All Metal Head For Greatest Durability Reduce Cut Injuries - Recessed Blade Prevents Contact With Fingers Reduce Damaged Goods In Boxes Or Packages As Cutting Surface is Shielded Excellent For Cutting: Cardboard, Cartons, Twine, Shrink Wrap Cutter etc.